A method for manufacturing a conductor

Abstract

A method for manufacturing a conductor, comprising: forming a conductor casting by low-pressure casting process, improving the conductivity of the conductor casting, machining, and polishing. The improvement of the conductivity of the conductor casting includes using a heating and quenching furnace. When the temperature reaches 540°C ± 5°C, keep it warm for 6 - 6.5 hours. After the heat preservation is completed, open the furnace door, immerse the conductor casting in water not lower than 60 ± 5°C for cooling, and the cooling time is 3 - 4 minutes. The temperature difference of the water temperature before and after quenching does not exceed 20°C ± 5°C; transfer the quenched conductor casting to a trolley-type aging furnace for aging treatment. Heat up to 220 ± 5°C and keep it warm for 5.5 - 6 hours. After the heat preservation is completed, turn off the power supply, open the furnace door, take out the conductor casting and place it in the air to cool naturally to room temperature; the conductivity of the conductor casting IACS ≥ 39%. The conductor product processed by the present invention has high conductivity, and the smooth conductor surface is obtained by polishing in different steps. The conductor product processed by the method of the present invention has high precision and high yield.

Description

Technical Field

[0001] The present invention belongs to the field of machining, and particularly relates to a method for manufacturing a conductor. Background Art

[0002] The conductor is used in a high-voltage switch. The high-voltage switch can not only cut off or close the no-load current and load current in the high-voltage circuit, but also cut off the overload current and short-circuit current through the action of the relay protection device when a system fault occurs. It has a quite perfect arc extinguishing structure and sufficient current-breaking capacity, and is an important part of the high-voltage circuit. As the main component of the high-voltage switch, the conductor is used together with the mutual inductor to realize the component for opening and closing the conductive loop, ensuring the normal use of the high-voltage circuit breaker.

[0003] The main function of the conductor is to conduct current, and it must have sufficient conductivity to ensure that the temperature rise of the high-voltage electrical equipment meets the design requirements under normal working conditions. When the conductor conducts current, a certain electrodynamic force will be generated between them. In order to ensure that the conductor does not produce deformation or damage that affects its performance, the conductor must have sufficient mechanical properties such as tensile strength, yield strength, and elongation. Therefore, the conductor needs to have good internal and external quality.

[0004] It is required that the outer surface is polished smoothly with a smooth transition, and there are no air holes and pinholes above grade one on the silver-plated surface.

[0005] The conductivity requirement of the conductor is that the conductivity IACS ≥ 39%. With the continuous increase of power demand, the current-carrying capacity requirement of high-voltage electrical equipment is getting higher and higher. To improve the current-carrying capacity, it is necessary to increase the conductivity of the conductor. Conductivity is also called electrical conductivity, which is a measurement value representing the ability of a substance to transmit current. When a voltage is applied across the two ends of a conductor, its charge carriers will flow in a certain direction, thus generating an electric current.

[0006] The conductor structure (such as Figure 1 ) includes a support arm 191 and a cylindrical arm 192 connected to the inner end of the support arm 191. The included angle between the end face of the support arm 191 and the cylindrical arm 192 is a, where 0 < a < 90°. There is a central hole 193 in the middle of the connection between the support arm 191 and the cylindrical arm 192. There are through holes in the middle of both the support arm and the cylindrical arm. The size of the through holes, and the outer diameter of the cylindrical arm 192 is 100 mm.

[0007] The conductor structure is irregular and has many processing elements. The existing processing method is to use manual line drawing and multiple sets of jigs to clamp the conductor separately to complete the processing of each processing element, including the through holes and grooves in the middle of the cylindrical arm, the through holes and various irregular grooves in the cylindrical arm, the end face of the tail and the screw mounting holes. When the second set of jigs is used for clamping, the hole system processed by the first set of jigs and the outer shape of the conductor are used for positioning, and so on until the processing of each processing element is completed. In this processing method, if the error is too large during the previous processing, it will affect the accuracy of the next processing and result in a low accuracy of the final product.

[0008] How to ensure the quality of the product and improve the yield of the product is an urgent problem to be solved. Summary of the Invention

[0009] The purpose of the present invention is to overcome the above deficiencies of the prior art and provide a conductor manufacturing method with high processing efficiency and high processing accuracy.

[0010] The technical solution of the present invention is: a conductor manufacturing method, including the following steps:

[0011] 1) Adopt the low-pressure casting process to form a conductor casting; the casting process is: core making - melting (ZL101H) - low-pressure pouring - sand cleaning - sawing risers - cleaning and shoveling; the conductor casting includes a support arm and a cylindrical arm connected to the inner end of the support arm. The included angle between the end face of the support arm and the cylindrical arm is a, and there is a central hole in the middle of the connection between the support arm and the cylindrical arm.

[0012] 2) Improve the conductivity of the conductor casting:

[0013] Adopt a heating quenching furnace. When the temperature reaches 540°C ± 5°C, keep it warm for 6 - 6.5 hours. After the heat preservation is over, open the furnace door and immerse the conductor casting in water not lower than 60 ± 5°C for cooling. The cooling time is 3 - 4 minutes, and the temperature difference between the water temperature before and after quenching does not exceed 20°C ± 5°C;

[0014] Transfer the quenched conductor casting to a trolley-type aging furnace for aging treatment. Heat up to 220 ± 5°C, keep it warm for 5.5 - 6 hours. After the heat preservation is over, turn off the power, open the furnace door, take out the conductor casting and place it in the air to cool naturally to room temperature;

[0015] The conductivity of the conductor casting IACS ≥ 39%;

[0016] 3) Machining

[0017] Clamp the conductor casting on the conductor fixture, position the conductor casting with the side limiting points formed by the positioning block, 1 support column and the limiting column, and press the conductor casting tightly with the pressure plate. Install the bridge plate of the conductor fixture on the fourth axis of the vertical machining center LCV1370L, and align the conductor fixture: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and measure the head in the transverse, longitudinal directions of the bridge plate of the conductor fixture, and the vertical direction after the fourth axis is rotated 90°. If the error is controlled within 0.02 mm, it is qualified;

[0018] Level the conductor casting: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and make the head close to one end of the cylindrical arm of the conductor casting. When the head moves to the other end of the cylindrical arm of the conductor casting, the jump of its pointer is controlled within 0.1 mm; Use the outer shape of the conductor product to find the height from the two ends of the cylindrical arm and the center of the tail of the support arm to the tooling rotating plate, meeting the requirements of the product drawing;

[0019] The tool setting method is as follows: Install the edge finder on the spindle of the machining center, and use fine adjustment operation to make the probe slowly touch the four positions in the X and Y directions of the circumference of the small hole of the center hole to obtain the coordinate values, and then calculate the center position of the small hole; Remove the edge finder, install the cutting tool used for machining on the spindle, and move the tool end face close to the upper surface of the small hole end face along the Z direction to determine the Z coordinate, thereby determining the workpiece coordinate system. All programming and machining are carried out with reference to this coordinate system;

[0020] A machine the center hole. The center hole is a stepped hole. The upper and lower parts of the center hole are large holes, and the middle part of the center hole is a small hole. There are two annular grooves at both ends of the small hole;

[0021] B Machine the inner hole of the cylindrical arm

[0022] Flip the fourth axis, level the lower end face of the cylindrical arm, and use the distance value of 148 mm between the cutting tool tip and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the lower part of the inner hole of the cylindrical arm; Flip the fourth axis, level the upper end face of the cylindrical arm, and use the distance value of 148 mm between the cutting tool tip and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the upper part of the inner hole of the cylindrical arm;

[0023] C Rotate the rotating plate, insert the pin into the limiting hole, and after the air cylinder presses the rotating plate, flip the fourth axis of the vertical machining center to level the end face of the tail of the support arm and machine the tail of the support arm;

[0024] 4) Grinding.

[0025] The measurement of the conductivity is detected by an eddy current conductivity meter 7501A. First, calibrate the eddy current conductivity meter to align the reading on the conductivity dial with the conductivity of the standard test block. Then, measure the conductivity of the conductor. Place the probe on the tail end face of the support arm 191 of the conductor casting, rotate the conductivity dial until the meter pointer is zero, and the conductivity value can be read from the dial. Through the conversion formula, the relationship between conductivity and conductance is: 1 MS / m = 1.7241% IACS, and the measured value of the conductance is obtained. The conductor conductance IACS ≥ 39% is considered qualified.

[0026] The following steps are included in the lower part of the machined cylindrical arm inner hole:

[0027] (6) Use a multi-functional milling cutter to mill the lower end face of the cylindrical arm, with the machining length of L, the spindle speed of 2000 - 2500 r / min, and the feed rate of 200 - 250 mm / min;

[0028] (7) Use a rough boring tool to bore the lower port 1921 of the cylindrical arm, with the depth of the lower port being L + 2 ± 1 mm, the spindle speed of 1500 - 1800 r / min, and the feed rate of 100 - 150 mm / min;

[0029] (8) Use a slot milling cutter to cut the small ring groove at the end, with the spindle speed of 1500 - 1800 r / min and the feed rate of 150 - 200 mm / min;

[0030] (9) Use a grooving cutter to cut the large ring groove at the end, with the spindle speed of 2000 - 2500 r / min and the feed rate of 150 - 200 mm / min;

[0031] (10) Reverse bore the lower connecting hole, starting from a depth of H1 from the lower end face and boring to a distance of H2 from the lower end face; boring tool, with the spindle speed of 1500 - 1800 r / min and the feed rate of 200 - 250 mm / min;

[0032] (11) Use a milling cutter to chamfer the tops of the small and large ring grooves at the lower part, with the spindle speed of 1500 - 1800 r / min and the feed rate of 200 - 250 mm / min;

[0033] (12) Chamfer the lower port fillet; with the spindle speed of 1500 - 1800 r / min and the feed rate of 200 - 250 mm / min;

[0034] (13) Use a welded concave semi-circular milling cutter to chamfer the fillet at the end of the lower end face, with the spindle speed of 1500 - 1800 r / min and the feed rate of 200 - 250 mm / min.

[0035] The upper part of the inner hole of the cylindrical arm is processed as follows: Complete the processing of the upper part of the inner hole of the cylindrical arm according to steps (6)-(13); among them, the boring tool is used to reverse-bore the upper connecting hole, starting from a depth of H1 from the upper end face and boring to a distance of H3 from the upper end face, with the spindle speed of 1500-1800 r / min and the feed rate of 200-250 mm / min. H3 + H2 > 2L. Avoid tool marks on the inner hole of the cylindrical arm. The small ring groove is an annular rectangular groove, and the large ring groove is a U-shaped groove.

[0036] The step 4) of grinding includes: Machine grinding: Firmly clamp the grinding wheel to prevent the abrasive cloth from flying out and hurting people. Hold the conductor casting tightly with both hands and grind the side of the 80# emery cloth grinding wheel to prevent grinding deformation. Grinding parts: Except for the machined surface of the conductor casting, the outer surface of the rest of the conductor casting. Replace with a 150# emery grinding wheel for grinding. Grinding parts: Except for the machined surface of the conductor casting, the outer surface of the rest of the conductor casting. The grinding lines of each plane form an angle of not less than 10° with the 80# lines. Keep the as-cast shape of the conductor casting during grinding; Rough grinding: Place the conductor casting on the grinding workbench, then roll the 80# emery cloth on the power tool and install it firmly. Use the 80# emery cloth roll grinder to grind the unground parts. The grinding track should be in a large circular arc shape and no pauses are allowed in the middle. Use a new abrasive cloth roll edge or fine abrasive cloth roll to grind the dead corners that cannot be ground; It is prohibited to use a new abrasive cloth roll edge to grind any plane. The surface after grinding should be the grinding lines of the 80# abrasive cloth, the surface should be flat, there is no unevenness by hand feeling, and no concave pits formed by pauses can be seen visually. It is not allowed to have the surface of the casting blank; Fine grinding: Replace with a 150# emery cloth roll and repeat the grinding according to the rough grinding steps; Grinding with a surface grinder, bond the 80# emery cloth to the surface grinder; Hold the surface grinder and grind evenly, smoothly and continuously along the outer shape of the large surface of the conductor casting; Replace with a 150# emery cloth and repeat the grinding according to the rough grinding steps;

[0037] Fine grinding: Bond the scouring pad to the surface grinder and grind evenly, smoothly and continuously. All intersections of straight lines and arcs should be smoothly transitioned to obtain the finished product.

[0038] The conductor fixture includes a bridge plate and a rotating plate. The rotating plate is rotatably installed on the bridge plate. The rotating plate is provided with a positioning and supporting component for positioning the conductor, a pressing component for pressing the positioned conductor, a side limiting member, and a pressing cylinder for pressing the position of the rotating plate under the bridge plate; The positioning and supporting component has a positioning groove that matches the outer circle of the cylindrical arm for supporting the conductor and a supporting surface for supporting the arm of the conductor; The side limiting member abuts against the relief groove on the arm; The pressing component includes a pressing plate and a pressing rod; The rotating plate has a pin hole for locking the rotation angle; The rotating plate has an adjustment hole for pressing the rotating plate, and the bridge plate has a mounting hole corresponding to the adjustment hole. The middle part of the pull rod passes through the mounting hole and extends into the adjustment hole. The lower end of the pull rod is connected to the pressing cylinder, and the upper end of the pull rod has a pressing nut.

[0039] The positioning support assembly includes a positioning block and a support column. The positioning block has a positioning groove matching the outer circle of the cylindrical arm of the conductor, and the support column has a support surface. The middle of the bridge plate has a fixed shaft, and the rotating plate is rotatably mounted on the fixed shaft on the bridge plate through a bearing.

[0040] The side limiting member is a limiting column, and the upper end of the limiting column is against the side wall of the clearance hole.

[0041] According to the angular distribution of the conductor processing elements, the number of pin holes is set to 2, and the two pin holes for adjusting the rotation angle are arranged on a large circle centered on the center hole, the diameter of the small circle is Φ550mm, and a is 40°; there are more than two adjusting holes to ensure that the cylinder presses the rotating plate, and each adjusting hole is arranged on a small circle centered on the center hole, and the diameter of the small circle is Φ420mm.

[0042] The fixed shaft outer sleeve is matched with the inner ring of the bearing, and a positioning hole matched with the outer ring of the bearing is provided in the middle of the rotating plate.

[0043] The positioning groove is formed by a V-shaped notch on the positioning block. The positioning block is connected to the rotating plate by positioning pins and screws. A rectangular groove for making way is provided at the bottom of the V-shaped notch. The rectangular groove is mainly used to make way for the tip of the angle milling cutter. When the V-shaped block is made, the tip of the cutter is protected from being damaged when the angle milling cutter is used to mill the V-shaped surface. The bridge plate and the rotating plate are both provided with pin holes. When the pin holes of the bridge plate and the rotating plate are aligned to form a complete limiting hole, the pin is inserted into the limiting hole. Two groups of pin holes are provided in total. When limiting, only one group of pin holes is used.

[0044] The conductor product processed by the present invention has high conductivity, and a smooth conductor surface is obtained through polishing in different steps. The conductor product processed by the method of the present invention has high precision, high yield rate and stable processing quality.

[0045] By using a conductor fixture, the conductor to be processed can be clamped once and then subjected to multi-angle and multi-station machining, so that the conductor meets the requirements of machining accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the structure of the conductor;

[0047] Figure 2 is a schematic diagram of the structure of the conductor fixture;

[0048] Figure 3 yes Figure 2 The main view of

[0049] Figure 4 yes Figure 2 A top view of

[0050] Figure 5 yes Figure 1 sectional view of . Detailed implementation mode

[0051] Figures 2 - 4 In this invention, it includes a bridge plate 1 and a rotating plate 2. The rotating plate 2 is rotatably installed on the bridge plate 1. On the rotating plate 2, there are a positioning and supporting assembly for positioning the conductor 19, a pressing assembly for pressing the positioned conductor 19, and a side limiting member. Below the bridge plate 1, there is a pressing cylinder for pressing the position of the rotating plate 2.

[0052] The positioning and supporting assembly includes a positioning block 4 and a supporting column 17. On the positioning block 4, there is a positioning groove that matches the outer circle of the cylindrical wall of the conductor. On the supporting column 17, there is a supporting surface. The positioning groove is formed by a V-shaped notch on the positioning block 4. The positioning block 4 and the rotating plate 2 are connected by a positioning pin and screws. At the bottom of the V-shaped notch, there is a rectangular groove for making way. The function of the rectangular groove is mainly to make way for the tip of the angular milling cutter. When the V-shaped block is manufactured, when milling the V-shaped surface with an angular milling cutter, it can protect the tip from being easily damaged. In the middle of the bridge plate 1, there is a fixed shaft 20. The rotating plate 2 is rotatably installed at the fixed shaft 20 on the bridge plate 1 through a bearing. The side limiting member is a limiting column 18, and the upper end of the limiting column 18 abuts against the side wall of the relief hole. The side limiting member abuts against the relief hole on the support arm 191. The pressing assembly includes a pressing plate 12 and a pressing rod. On the rotating plate 2, there are pin holes for locking the rotation angle; there are 2 pin holes, and the two pin holes for adjusting the rotation angle are arranged on a large circumference centered on the central hole 193, and the diameter of the large circumference is Φ550mm. On the rotating plate 2, there are adjustment holes for pressing the rotating plate 2. On the bridge plate 1, there are installation holes corresponding to the adjustment holes. The middle part of the pull rod passes through the installation hole and extends into the adjustment hole. The lower end of the pull rod is connected to the pressing cylinder, and the upper end of the pull rod has a pressing nut. There are more than two adjustment holes to ensure that the cylinder presses the rotating plate. Each adjustment hole is arranged on a small circumference centered on the central hole 193, and the diameter of the small circumference is Φ420mm. The outer sleeve of the fixed shaft 20 is matched with the inner ring of the bearing, and there is a positioning hole on the middle part of the rotating plate 2 that is matched with the outer ring of the bearing.

[0053] During use, after machining the conductor cylindrical arm 192, loosen the pressing cylinder, pull out the pin 3, rotate the rotating plate 2 to drive the conductor to another machining position. When the pin holes of the bridge plate 1 and the rotating plate 2 are aligned to form a complete limiting hole, insert the pin 3 into the limiting hole.

[0054] This fixture can also clamp other-shaped conductors similar to the structure of this conductor. The spare limiting column 21 is used for the limitation of other-shaped conductors. Through the lifting ring installed at the hole 22, the fixture can be lifted by a lifting tool.

[0055] The manufacturing method of the conductor of this invention includes the following steps (the length unit in the following steps is all mm):

[0056] 1) Form a conductor casting by low-pressure casting process; the casting process is: core making - melting (ZL101H) - low-pressure pouring - sand cleaning - sawing riser - cleaning and scraping;

[0057] 2) Improvement of the conductivity of the conductor casting:

[0058] Adopt a heating and quenching furnace. When the temperature reaches 540°C ± 5°C, keep it warm for 6 - 6.5 hours. After the heat preservation is over, open the furnace door, immerse the conductor casting in water not lower than 60 ± 5°C for cooling, the cooling time is 3 - 4 minutes, and the temperature difference of the water temperature before and after quenching does not exceed 20°C ± 5°C;

[0059] Transfer the quenched conductor casting to a trolley-type aging furnace for aging treatment. Heat up to 220 ± 5°C, keep it warm for 5.5 - 6 hours. After the heat preservation is over, turn off the power, open the furnace door, take out the conductor casting and place it in the air to cool naturally to room temperature;

[0060] The conductivity is measured by an eddy current conductivity meter (7501A). First, calibrate the eddy current conductivity meter to align the conductivity dial reading with the conductivity of the standard test block. Then, measure the conductivity of the conductor. Place the probe on the end face of the arm 191 tail of the conductor casting, rotate the conductivity dial to make the meter pointer zero, and the conductivity value can be read from the dial. Through the conversion formula, the relationship between conductivity and conductivity: 1 MS / m = 1.7241% IACS, the measured value of conductivity is obtained. The conductor conductivity IACS ≥ 39% is qualified.

[0061] 3) Machining

[0062] Clamp the conductor casting on the conductor fixture, position the conductor casting with the side limit points formed by the positioning block 4, 1 support column 17 and the limit column 18, and press the conductor casting with a pressing plate. Install the bridge plate 1 of the conductor fixture on the fourth axis of the vertical machining center LCV1370L, and align the conductor fixture: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and measure the head in the horizontal and vertical directions of the bridge plate 1 of the conductor fixture and in the vertical direction after the fourth axis is rotated 90°. The error is controlled within 0.02 mm to be qualified;

[0063] Level the conductor casting: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and make the head close to one end of the cylindrical arm 192 of the conductor casting. When the head moves to the other end of the cylindrical arm 192 of the conductor casting, the jump of its pointer is controlled within 0.1 mm; Find the height from the two ends of the cylindrical arm 192 and the center of the tail of the arm 191 to the tooling rotating plate 2 according to the outer shape of the conductor product to meet the requirements of the product drawing;

[0064] The tool setting method is as follows: Install the edge finder on the spindle of the machining center. Using fine-tuning operation, slowly bring the probe into contact with four positions on the circumference of the small hole of the center hole 193 in the X and Y directions to obtain the coordinate values, and then calculate the center position of the small hole 193. Remove the edge finder, install the cutting tool used for machining on the spindle, and move the tool end face close to the upper surface of the end face of the small hole 193 along the Z direction to determine the Z coordinate, thereby determining the workpiece coordinate system. All programming and machining are carried out with reference to this coordinate system;

[0065] A. Machine the center hole 193. The center hole 193 is a stepped hole. The upper and lower parts of the center hole 193 are large holes, the middle part of the center hole 193 is a small hole, and there are two annular grooves at both ends of the small hole;

[0066] B. Machine the inner hole of the cylindrical arm 192 (such as Figure 5 )

[0067] Flip the fourth axis, level the lower end face of the cylindrical arm 192, and use the distance value of 148 mm between the tip of the machining tool and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the lower part of the inner hole of the cylindrical arm 192; Flip the fourth axis, level the upper end face of the cylindrical arm 192, and use the distance value of 148 mm between the tip of the machining tool and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the upper part of the inner hole of the cylindrical arm 192;

[0068] (6)Use a multi-functional milling cutter to mill the lower end face 1920 of the cylindrical arm 192. The machining length is L, the spindle speed is 2000 - 2500 r / min, and the feed rate is 200 - 250 mm / min;

[0069] (7)Use a rough boring cutter to bore the lower port 1921 of the cylindrical arm 192. The depth of the lower port 1921 is L + 2 ± 1 mm, the spindle speed is 1500 - 1800 r / min, and the feed rate is 100 - 150 mm / min;

[0070] (8)Use a slot milling cutter to cut the lower small ring groove 1922. The spindle speed is 1500 - 1800 r / min, and the feed rate is 150 - 200 mm / min;

[0071] (9)Use a grooving cutter to cut the lower large ring groove 1923. The spindle speed is 2000 - 2500 r / min, and the feed rate is 150 - 200 mm / min;

[0072] (10) Counter-bore the lower connecting hole 1924, starting from a depth of H1 from the lower end face and boring to a distance of H2 from the lower end face; Use a boring cutter, the spindle speed is 1500 - 1800 r / min, and the feed rate is 200 - 250 mm / min;

[0073] (11)Use a milling cutter to chamfer the tops of the lower small ring groove and large ring groove. The spindle speed is 1500 - 1800 r / min, and the feed rate is 200 - 250 mm / min;

[0074] (12) The falling port 1921 has rounded corners; the spindle speed is 1500 - 1800 r / min, and the feed rate is 200 - 250 mm / min;

[0075] (13) The welded concave semi - circular milling cutter has rounded corners at the lower end face of the end part, the spindle speed is 1500 - 1800 r / min, and the feed rate is 200 - 250 mm / min.

[0076] Machining the upper part of the inner hole of the cylindrical arm 192 includes the following steps: Complete the machining of the upper part of the inner hole of the cylindrical arm 192 according to steps (6) - (13); Among them, the boring tool is used for reverse boring of the upper connecting hole 1925, starting from a depth of H1 from the upper end face and boring to a distance of H3 from the upper end face, the spindle speed is 1500 - 1800 r / min, and the feed rate is 200 - 250 mm / min; H3 + H2 > 2L. Among them, the small ring groove 1922 is an annular rectangular groove, and the large ring groove 1923 is a U - shaped groove.

[0077] 4) Grinding:

[0078] Machine grinding: Firmly clamp the grinding wheel to prevent the abrasive cloth from flying out and hurting people. Hold the conductor casting firmly with both hands and grind the side of the 80# emery cloth grinding wheel to prevent grinding deformation. Grinding parts: Except for the machined surface of the conductor casting, the remaining outer surface of the conductor casting. Replace with a 150# emery grinding wheel for grinding. Grinding parts: Except for the machined surface of the conductor casting, the remaining outer surface of the conductor casting. The grinding lines of each plane form an angle of not less than 10° with the 80# lines, and keep the as - cast shape of the conductor casting during grinding;

[0079] Rough grinding: Place the conductor casting on the grinding workbench, then firmly install the 80# emery cloth roll on the electric tool, and use the 80# emery cloth roll grinding machine to grind the unground parts. The grinding track should be in a large circular arc shape and no pause is allowed in the middle. Use a new abrasive roll edge or a fine abrasive roll to grind the dead - angle parts that cannot be ground; It is prohibited to use a new abrasive roll edge to grind any plane. The ground surface should be the grinding lines of the 80# abrasive cloth, the surface should be flat, there is no unevenness to the touch, and no concave pits formed by pauses can be seen visually. It is not allowed to have the surface of the casting blank;

[0080] Fine grinding: Replace with a 150# emery cloth roll and repeat the grinding according to the rough - grinding steps; Use a surface grinder for grinding, bond the 80# emery cloth on the surface grinder; Hold the surface grinder and grind evenly, smoothly and continuously along the outer shape of the large surface of the conductor casting; Replace with a 150# emery cloth and repeat the grinding according to the rough - grinding steps;

[0081] Fine grinding: Bond the scouring pad on the surface grinder and grind evenly, smoothly and continuously. All intersections of straight lines and arcs should have smooth transitions to obtain the finished product.

Claims

1. A method for manufacturing a conductor, characterized in that: It includes the following steps: 1) Form a conductor casting by low-pressure casting process; the conductor casting includes a support arm (191) and a cylindrical arm (192) connected to the inner end of the support arm (191). The included angle between the end face of the support arm (191) and the cylindrical arm (192) is a. There is a central hole (193) in the middle of the connection between the support arm (191) and the cylindrical arm (192); 2) Improve the conductivity of the conductor casting: Use a heating and quenching furnace. When the temperature reaches 540°C ± 5°C, keep it warm for 6 - 6.5 hours. After the heat preservation ends, open the furnace door and immerse the conductor casting in water not lower than 60 ± 5°C for cooling. The cooling time is 3 - 4 minutes, and the temperature difference between the water temperature before and after quenching does not exceed 20°C ± 5°C; Transfer the quenched conductor casting to a trolley-type aging furnace for aging treatment. Heat up to 220 ± 5°C and keep it warm for 5.5 - 6 hours. After the heat preservation ends, turn off the power, open the furnace door, take out the conductor casting and place it in the air to cool naturally to room temperature; The conductivity of the conductor casting IACS ≥ 39%; 3) Machining Clamp the conductor casting on the conductor fixture. Locate the conductor casting with the side limiting points formed by the positioning block (4), 1 support column (17) and the limiting column (18), and press the conductor casting with a pressing plate. Install the bridge plate (1) of the conductor fixture on the fourth axis of the machining center and align the conductor fixture: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and measure the head in the horizontal, vertical directions of the bridge plate (1) of the conductor fixture and the vertical direction after the fourth axis is rotated 90°. If the error is controlled within 0.02 mm, it is qualified; Level the conductor casting: Use a magnetic base to suck the dial indicator on the spindle of the machining center, and make the head close to one end of the cylindrical arm (192) of the conductor casting. When the head moves to the other end of the cylindrical arm (192) of the conductor casting, the jump of its pointer is controlled within 0.1 mm; Find the height from the two ends of the cylindrical arm (192) and the center of the tail of the support arm (191) to the tooling rotating plate (2) according to the outer shape of the conductor product to meet the requirements of the product drawing; The tool setting method is: Install the edge finder on the spindle of the machining center, and use fine-tuning operation to make the probe slowly touch the four positions in the X and Y directions of the circumference of the small hole of the central hole (193) to obtain the coordinate values, and then calculate the center position of the small hole (193); Remove the edge finder, install the cutting tool used for machining on the spindle, and move the tool end face close to the upper surface of the end face of the small hole (193) along the Z direction to determine the Z coordinate, so as to determine the workpiece coordinate system; A Machine the central hole (193). The central hole (193) is a stepped hole. The upper and lower parts of the central hole (193) are large holes, and the middle part of the central hole (193) is a small hole. There are two annular grooves at both ends of the small hole; B Machine the inner hole of the cylindrical arm (192) Flip the four-axis, level the lower end face of the cylindrical arm (192), and use the distance value between the tip of the machining tool and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the lower part of the inner hole of the cylindrical arm (192); Flip the four-axis, level the upper end face of the cylindrical arm (192), and use the distance value between the tip of the machining tool and the origin of the workpiece coordinate system in the Z direction as the length compensation value to machine the upper part of the inner hole of the cylindrical arm (192). C Rotate the rotating plate (2), insert the pin (3) into the limit hole, and after the air cylinder presses the rotating plate, flip the four-axis of the vertical machining center to level the tail end face of the support arm (191) and machine the tail of the support arm (191). 4) Grinding.

2. The method for manufacturing a conductor according to claim 1, characterized in that: The measurement of the conductivity is detected by an eddy current conductivity meter. First, calibrate the eddy current conductivity meter to align the reading of the conductivity dial with the conductivity of the standard test block. Then, measure the conductivity of the conductor. Place the probe on the tail end face of the support arm (191) of the conductor casting, rotate the conductivity dial to make the meter pointer zero, and the conductivity value can be read from the dial. Through the conversion formula, the relationship between conductivity and electrical conductivity: 1 MS / m = 1.7241% IACS, the measured value of the electrical conductivity is obtained. The conductor electrical conductivity IACS ≥ 39% is qualified.

3. The method for manufacturing a conductor according to claim 1, characterized in that: The following steps are included in machining the lower part of the inner hole of the cylindrical arm (192): (6) Use a multi-functional milling cutter to mill the lower end face (1920) of the cylindrical arm (192), with a machining length of L, a spindle speed of 2000 - 2500 r / min, and a feed rate of 200 - 250 mm / min; (7) Use a rough boring tool to bore the lower port (1921) of the cylindrical arm (192). The depth of the lower port (1921) is L + 2 ± 1 mm, the spindle speed is 1500 - 1800 r / min, and the feed rate is 100 - 150 mm / min; (8) Use a slot milling cutter to cut the small ring groove (1922) at the end, with a spindle speed of 1500 - 1800 r / min and a feed rate of 150 - 200 mm / min; (9) Use a grooving cutter to cut the large ring groove (1923) at the end, with a spindle speed of 2000 - 2500 r / min and a feed rate of 150 - 200 mm / min; (10) Reverse bore the lower connecting hole (1924), starting from a depth of H1 from the lower end face and boring to a distance of H2 from the lower end face; boring tool, spindle speed 1500 - 1800 r / min, feed rate 200 - 250 mm / min; (11) Use a milling cutter to chamfer the tops of the small and large ring grooves at the lower part, with a spindle speed of 1500 - 1800 r / min and a feed rate of 200 - 250 mm / min; (12) Chamfer the fillet of the lower port (1921); spindle speed 1500 - 1800 r / min, feed rate 200 - 250 mm / min; (13) Use a welded concave semi-circular milling cutter to chamfer the fillet at the end of the lower end face, with a spindle speed of 1500 - 1800 r / min and a feed rate of 200 - 250 mm / min.

4. The method for manufacturing a conductor according to claim 1, characterized in that: The upper part of the inner hole of the cylindrical arm (192) is processed by the following steps: The upper part of the inner hole of the cylindrical arm (192) is processed according to steps (6)-(13); wherein, the boring tool boringly machines the upper connecting hole (1925), starting from a depth of H1 from the upper end face and boring to a distance of H3 from the upper end face, with the spindle speed of 1500 - 1800 r / min and the feed rate of 200 - 250 mm / min; H3 + H2 > 2L.

5. The method for manufacturing a conductor according to claim 1, characterized in that: The step 4) of grinding includes: Machine grinding: firmly clamp the grinding wheel, hold the conductor casting with both hands firmly, and grind the side of the 80# emery cloth grinding wheel; the grinding part: the outer surface of the conductor casting except the machined surface of the conductor casting, replace it with a 150# emery grinding wheel for grinding; the grinding part: the outer surface of the conductor casting except the machined surface of the conductor casting, and the grinding lines of each plane form an angle of not less than 10° with the 80# lines, and keep the as-cast shape of the conductor casting during grinding; Rough grinding: Place the conductor casting on the grinding workbench, then firmly install the 80# emery cloth roll on the electric tool, and use the 80# emery cloth roll grinding machine to grind the unground parts. The grinding trajectory should be in a large circular arc shape and no pause is allowed in the middle. Use a new abrasive roll edge or a fine abrasive roll to grind the dead corners that cannot be ground; it is prohibited to use a new abrasive roll edge to grind any plane. The ground surface should be the grinding lines of the 80# emery cloth, the surface should be flat, there is no unevenness by hand feeling, and no concave pits formed by pauses can be seen visually, and the surface of the casting blank is not allowed to exist; Fine grinding: Replace it with a 150# emery cloth roll and repeat the grinding according to the rough grinding steps; Grind with a surface grinder, bond the 80# emery cloth on the surface grinder; hold the surface grinder and grind evenly, smoothly and continuously along the outer shape of the large surface of the conductor casting; replace it with a 150# emery cloth and repeat the grinding according to the rough grinding steps; Fine grinding: Bond the scouring pad on the surface grinder and grind evenly, smoothly and continuously. All intersections of straight lines and arcs should be smoothly transitioned to obtain the finished product.

6. The method for manufacturing a conductor according to claim 1, characterized in that: The conductor fixture includes a bridge plate (1) and a rotating plate (2). The rotating plate (2) is rotatably installed on the bridge plate (1). The rotating plate (2) is provided with a positioning and supporting component for positioning the conductor (19), a pressing component for pressing the positioned conductor (19), a side limiting member, and there is a pressing cylinder under the bridge plate (1) for pressing the position of the rotating plate (2); The positioning and supporting component has a positioning groove matching the outer circle of the cylindrical arm (192) for supporting the conductor (19) and a supporting surface for supporting the supporting arm (191) of the conductor; The side limiting member abuts against the relief groove on the supporting arm (191); The pressing component includes a pressing plate and a pressing rod; There is a pin hole for locking the rotation angle on the rotating plate (2); There is an adjusting hole for pressing the rotating plate (2) on the rotating plate (2), and there is a mounting hole corresponding to the adjusting hole on the bridge plate (1). The middle part of the pull rod passes through the mounting hole and extends into the adjusting hole. The lower end of the pull rod is connected to the pressing cylinder, and there is a pressing nut at the upper end of the pull rod.

7. The method for manufacturing a conductor according to claim 6, wherein: The positioning and supporting assembly includes a positioning block (4) and a supporting column (17). The positioning block (4) has a positioning groove that matches the outer circle of the cylindrical arm of the conductor, and the upper surface of the supporting column (17) is a supporting surface; A fixed shaft (20) is provided in the middle of the bridge plate (1), and the rotating plate (2) is rotatably mounted on the fixed shaft (20) of the bridge plate (1) through a bearing; The side limiting member is a limiting column (18), and the upper end of the limiting column (18) abuts against the side wall of the relief hole.

8. The method for manufacturing a conductor according to claim 7, wherein: According to the angular distribution of the conductor processing elements, two pin holes are provided, and the two pin holes for adjusting the rotation angle are arranged on a large circumference centered on the center hole; More than two adjusting holes are provided, and each adjusting hole is arranged on a small circumference centered on the center hole (193).

9. The method for manufacturing a conductor according to claim 8, wherein: The outer sleeve of the fixed shaft (20) is matched with the inner ring of the bearing, and the middle part of the rotating plate (2) has a positioning hole that matches the outer ring of the bearing.

10. The method for manufacturing a conductor according to claim 9, wherein: The positioning groove is formed by a V-shaped notch on the positioning block (4). The positioning block (4) and the rotating plate (2) are connected by a positioning pin and a screw, and a rectangular groove for making way is provided at the bottom of the V-shaped notch; Both the bridge plate (1) and the rotating plate (2) are provided with pin holes. When the pin holes of the bridge plate (1) and the rotating plate (2) are aligned to form a complete limiting hole, the plug pin (3) is inserted into the limiting hole.

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